Optical trocar with scope holding assembly

ABSTRACT

An optical access apparatus for receiving an endoscope to permit visualization during passage through tissue includes an access member dimensioned for insertion through body tissue. The access member defines a longitudinal axis and has a longitudinal opening for receiving an endoscope. The access member has a closed penetrating end adapted to pass through tissue. The closed penetrating end is transparent to permit visualization of tissue with the endoscope. The optical access apparatus further includes a locking collet coaxially mounted relative to the longitudinal axis of the access member and a manual member mounted adjacent the locking collet and operatively engageable therewith. The locking collet has internal surfaces defining an internal passage to permit passage of the surgical instrument. The manual member is adapted for rotational movement about the longitudinal axis to reduce an internal dimension of the internal passage of the locking collet to cause the internal surfaces of the locking collet to securely engage the surgical instrument.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.12/882,581, filed Sep. 15, 2010, which is a continuation of U.S.application Ser. No. 11/103,892, filed Apr. 12, 2005, now U.S. Pat. No.7,824,327, the contents of the each application being incorporated byreference herein in their entirety.

BACKGROUND

1. Technical Field

The present invention relates to an apparatus for penetration of bodytissue. More particularly, the present invention relates to an opticaltrocar including a scope holding mechanism for selectively securing anendoscope, laparoscope, or surgical instruments within the opticaltrocar to provide visualization during penetration of the peritoneum orother body tissue.

2. Background of Related Art

In endoscopic surgical procedures, surgery is performed in any hollowviscus of the body through a small incision or through narrow endoscopictubes (cannulas) inserted through a small entrance wound in the skin. Inlaparoscopic procedures, surgery is performed in the interior of theabdomen. Laparoscopic and endoscopic procedures often require thesurgeon to act on organs, tissues, and vessels far removed from theincision, thereby requiring that any instruments used in such proceduresbe of sufficient size and length to permit remote operation. Typically,after the surgical region is insufflated, a trocar is used to puncturethe body cavity and includes a cannula which remains in place for useduring the laparoscopic procedure. Generally, a trocar includes a styletor obturator having a sharp tip for penetrating the body cavity. Anexample of a known trocar is described in commonly assigned U.S. Pat.No. 4,601,710 to Moll. Most currently used trocars rely on protectivetubes or relative retraction of the tip to prevent inadvertent contactwith tissue.

SUMMARY

Accordingly, the present disclosure relates to further improvement inaccessing/penetrating body tissue during a surgical procedure,preferably, a laparoscopic procedure. The present disclosure is directedto a surgical system including an optical trocar for directly observingthe penetration of the peritoneum or other body portions. The opticaltrocar includes a transparent window for passing optical images to animaging system of an endoscope or laparoscope positioned within theoptical trocar. In addition, the present invention provides an improvedpenetrating end for penetration of body tissue.

In one preferred embodiment, an optical access apparatus for receivingan endoscope to permit visualization during passage through tissueincludes an access member which is dimensioned for insertion throughbody tissue. The access member defines a longitudinal axis and has alongitudinal opening for receiving an endoscope. The access member has aclosed penetrating end adapted to pass through tissue. The closedpenetrating end is transparent to permit visualization of tissue withthe endoscope. The optical access apparatus further includes a lockingcollet coaxially mounted relative to the longitudinal axis of the accessmember and a manual member mounted adjacent the locking collet andoperatively engageable therewith. The locking collet has internalsurfaces defining an internal passage to permit passage of theendoscope. The manual member is adapted for rotational movement aboutthe longitudinal axis to reduce an internal dimension of the internalpassage of the locking collet to cause the internal surfaces of thelocking collet to securely engage the endoscope. The manual member maydefine a central aperture for at least partial reception of the lockingcollet.

In one embodiment, the locking collet is adapted for rotational movementrelative to the longitudinal axis whereby rotational movement of themanual member causes the locking collet to correspondingly rotate. Thelocking collet is further adapted for longitudinal movement relative tothe manual member. Preferably, the locking collet and the manual memberinclude corresponding camming surfaces whereby upon longitudinalmovement of the locking collet relative to the manual member the cammingsurfaces cooperate to reduce the internal dimension of the internalpassage of the locking collet. Cam slot means for effecting longitudinalmovement of the locking collet upon rotational movement thereof may alsobe provided.

In an alternate embodiment, the locking collet is fixed relative to theaccess member whereby the manual member is adapted to rotate about thelocking collet. The locking collet and the manual member includecorresponding camming surfaces whereby, upon rotational movement of themanual member relative to the collet, the camming surfaces cooperate toreduce the internal dimension of the internal passage of the lockingcollet.

The penetrating end defines a tapered configuration having opposedconcave surfaces and opposed convex surfaces. This alternating concaveand convex relationship provides a reduced profile to facilitate passagethrough tissue.

The present disclosure is also directed to a surgical system includingan endoscope and an optical access apparatus for reception of theendoscope. The optical access apparatus includes a housing defining alongitudinal axis, a locking collet mounted to the housing and coaxiallymounted relative to the longitudinal axis and having internal surfacesdefining an internal passage to permit passage of the endoscope, and amanual member coaxially mounted about the locking collet. The manualmember is adapted for rotational movement about the longitudinal axis tocompress the locking collet to reduce an internal dimension of theinternal passage of the locking collet to thereby cause the internalsurfaces of the locking collet to securely engage the endoscope infrictional engagement therewith. The optical access apparatus also hasan elongated access member extending from the housing and having alongitudinal opening for receiving the endoscope. The access member hasa closed penetrating end adapted to pass through tissue. The closedpenetrating end is transparent to permit visualization of tissue withthe endoscope.

In one embodiment, the locking collet is adapted for rotational andlongitudinal movement relative to the longitudinal axis wherebyrotational movement of the manual member causes the locking collet torotate and move in a longitudinal direction. The manual memberpreferably includes internal compressive surfaces adapted to engage thelocking collet during longitudinal movement of the locking collet toreduce the internal dimension of the internal passage of the lockingcollet.

In another embodiment, the locking collet is fixed within the housingand the manual member is adapted to rotate about the locking collet. Themanual member includes internal compressive surfaces adapted to engagethe locking collet during rotational movement of the manual member toreduce the internal dimension of the internal passage of the lockingcollet. The manual member includes internal cam shelves. The internalcam shelves are accommodated within outer recesses of the locking colletwhen in an initial position of the manual member whereby, uponrotational movement of the manual member to an actuated position, thecam shelves traverse the grooves to engage outer cam surfaces of thelocking collet.

A method of using the system is also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiment(s) given below, serve toexplain the principles of the disclosure, wherein:

FIG. 1 is a perspective view of a surgical system in accordance with theprinciples of the present disclosure illustrating the optical accessapparatus and an endoscope for insertion within the access apparatus;

FIG. 2 is a perspective view of the optical access apparatus of thesurgical system in accordance with the embodiment of FIG. 1;

FIG. 3 is a perspective view with parts separated of the optical accessapparatus in accordance with the embodiment of FIGS. 1 and 2,illustrating components of the access member and the housing;

FIG. 4 is a side cross-sectional view of the optical access apparatus inaccordance with the embodiment of FIGS. 1-3 and taken along the lines4-4 of FIG. 2, illustrating the manual member and the collet in aninitial position;

FIG. 5 is a side cross sectional view of the optical access apparatus inaccordance with the embodiment of FIGS. 1-4 and taken along the lines5-5 of FIG. 2;

FIGS. 6 and 7 are enlarged perspective views of the penetrating end ofthe access member of the optical access apparatus in accordance with theembodiment of FIGS. 1-5;

FIG. 8 is an enlarged perspective view of the optical access apparatuswith the endoscope positioned therein in accordance with the embodimentif FIGS. 1-7, illustrating the manual member in an initial condition;

FIG. 9 is a side cross-sectional view similar to the view of FIG. 4 withthe endoscope positioned within the optical access apparatus inaccordance with the embodiment of FIGS. 1-8;

FIG. 10 is a view similar to the view of FIG. 8 illustrating the manualmember of the optical access apparatus in an actuated position securingthe endoscope in accordance with the embodiment of FIGS. 1-9;

FIG. 11 is a view similar to the view of FIG. 9 further illustrating thecollet securing the endoscope upon movement of the manual member to theactuated position in accordance with the embodiment of FIGS. 1-10;

FIG. 12 is a perspective view illustrating an endoscope positionedwithin the optical access apparatus and accessing body tissue;

FIG. 13 is a perspective view of an alternate optical access apparatusfor use with the system of the present disclosure;

FIG. 14 is a perspective view with parts separated of the optical accessapparatus in accordance with the embodiment of FIG. 13, illustratingcomponents of the access member and the housing;

FIG. 15 is a perspective view of the collet mounted to the elongatemember of the optical access apparatus in accordance with the embodimentof FIGS. 13 and 14;

FIG. 16 is a perspective view of the manual member of the optical accessapparatus in accordance with the embodiment if FIGS. 13-15, illustratingthe camming surfaces of the manual member;

FIG. 17 is an enlarged perspective view of the optical access apparatuswith the endoscope positioned therein in accordance with the embodimentif FIGS. 13-16, illustrating the manual member in an initial condition;

FIG. 18 is a side cross-sectional view of the optical access apparatuswith the endoscope positioned therein in accordance with the embodimentof FIGS. 13-17, illustrating the manual member in an initial position;

FIG. 19 is an axial cross-section view of the housing of the opticalaccess apparatus in accordance with the embodiment of FIGS. 13-18further illustrating the manual member in the initial position;

FIG. 20 is a view similar to the view of FIG. 17 illustrating movementof the manual member to the actuated position in accordance with theembodiment of FIGS. 13-19;

FIG. 21 is a view similar to the view of FIG. 18 further illustratingmovement of the manual member to the actuated position in accordancewith the embodiment of FIGS. 13-20; and

FIG. 22 is a view similar to the view of FIG. 19 further illustratingmovement of the manual member to the actuated position in accordancewith the embodiment of FIGS. 13-21.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to FIG. 1, there is illustrated a surgical system inaccordance with the present disclosure. System 10 includes twocomponents, namely, optical access apparatus 100 and endoscope 200 whichis positionable within the access apparatus 100. System 10 hasparticular application in accessing the abdominal cavity during alaparoscopic procedure. Endoscope 200 is positioned within opticalaccess apparatus 100 and the assembled unit is advanced through anincision and into the body cavity. During the advancement within tissue,endoscope 200 permits constant visualization of the neighboring tissuethereby providing confirmation upon entering into the body cavity whilealso preventing undesired contact or engagement with any underlyingorgans. Alternatively, endoscope 200 may be positioned within opticalaccess apparatus 100 after the optical access apparatus 100 has beenadvanced into the body cavity.

Endoscope 200 may be any conventional scope suitable for endoscopicapplications including, e.g., a laparoscope, arthroscope, colonoscope,etc. In one preferred embodiment, endoscope 200 may be the scopedisclosed in commonly assigned U.S. Pat. No. 5,412,504 to Leiner, theentire contents of which are hereby incorporated by reference. Endoscope200 incorporates an optical train or lens arrangement which is capableof transmitting an image of an object from the distal or objective lensthrough the eyepiece or monitor for viewing by the surgeon. Thus,although FIG. 1 shows an endoscope 200 with an eyepiece at its proximalend, the endoscope 200 additionally or alternatively may be connected toa monitor. Further details of endoscope 200 may be ascertained byreference to the '504 patent.

Referring now to FIGS. 2-4, optical access apparatus 100 of the system10 will be discussed. Access apparatus 100 includes housing 102,consisting of several assembled components, and elongate member 104extending distally from the housing 102. Access apparatus 100 defineslongitudinal axis “a”. In one preferred embodiment, housing 102incorporates the following components: manual manipulative member 106,collet 108 which is positioned within the manual member 106, skirt 110,and housing plate 112. As appreciated, these components are assembledtogether to define a single unit which is subsequently attached toelongate or access member 104.

Manual member 106 is adapted to rotate about the longitudinal axis “a”to secure endoscope 200 in a desired longitudinal position within theaccess apparatus 100. In this regard, manual member 106 defines an outerscalloped surface 114 advantageously dimensioned to be gripped by thesurgeon. Manual member 106 has central aperture 116 extendingtherethrough which at least partially receives collet 108, and aplurality of axially depending tabs 118 positioned about thelongitudinal axis “a” in spaced relation. Tabs 118 are engageable withskirt 110 to mount the manual member 106 to the skirt 110. Manual member106 also defines a pair of diametrically opposed internal axial slots120 adjacent central aperture 116. Manual member 106 has internalinclined, e.g., frusto-conical, camming surface 122 at the proximal endof the manual member 106.

Referring still to FIGS. 2-4, collet 108 includes proximal collar 124which is separated or divided into collar sections 124 a by partialslots 126. The outer surface of proximal collar 124 defines inclined orcamming surfaces 128 which are obliquely arranged relative to thelongitudinal axis “a” of apparatus 100. As to be appreciated, collarsections 124 a are adapted to be deflected radially inwardly relative tothe axis “a” to frictionally engage endoscope 200 through cooperation ofcamming surfaces 122, 128 of manual member 106 and collet 108,respectively. Collet 108 further defines a pair of diametrically opposedcam pins 130. Cam pins 130 are received within axial slots 120 of manualmember 106 and provide axial movement to collet 108 upon rotation ofmanual member 106. Cam pins 130 are retained within slots 120 andtraverse the slots 120 in a longitudinal direction upon rotationalmovement of manual member 106 and collet 108.

With reference now to FIGS. 2-5, skirt 110 includes proximal or upperannular wall 132 and lower annular wall 134 interconnected byintermediate sloped wall 136. Skirt 110 defines internal shoulder 138(FIG. 5) extending transversely relative to axis “a”. Shoulder 138 isengaged by locking tabs 118, specifically, transverse shelves 118 a ofthe locking tabs 118, of manual member 106 in the assembled condition ofthe components to secure skirt 110 and manual member 106. FIG. 5illustrates in detail the relationship of locking tabs 118 and shoulder138. Skirt 110 further defines a plurality of rectangular shapedopenings 140 extending through sloped wall 136.

Housing plate 112 includes central aperture 142 which is generalalignment with the longitudinal axis “a” and axial tabs 144. Tabs 144possess shelves 144 a which are received within rectangular openings 140of skirt 110 to secure housing plate 112 to the skirt 110. FIG. 4illustrates in detail the relationship of tabs 144 of housing plate 112and rectangular openings 140 of skirt 110. Housing plate 112 furtherdefines a plurality of internal projections 146. Projections 146 assistin securing plate 112 to elongate member 104 and to prevent rotationalmovement of the plate 112 relative to the elongate member 104.

Referring still to FIGS. 2-5, elongate or access member 104 will bediscussed. Elongate member 104 includes flange 148 adjacent its proximalend. Flange 148 is generally disc-shaped and defines two opposed radialslots 150. Radial slots 150 accommodate projections 146 of plate 112 inthe assembled condition of the components to rotationally fix thecomponents. As shown, flange 148 rests on housing plate 112 whenassembled within housing 102. Elongate member 104 further defines a pairof angled cam slots 152 extending completely through the wall ofelongate member 104 proximal of flange 148. Cam slots 152 receive campins 130 of collet 108 and are dimensioned to permit the pins 130 totraverse the slots 152 upon rotational movement of manual member 106 andthe collet 108. As appreciated, during this rotational movement ofcollet 108, collet 108 is driven in a general downward directionrelative to elongate member 104 through the sloped arrangement of camslots 152. Elongate member 104 further defines a pair of partialinternal angled grooves 154 in its interior surface proximal of flange146. Grooves 154 facilitate assembly of collet 108 within elongatemember 104 by receiving cam pins 130 of the collet 108 during insertionof the collet 108 within the elongate member 104.

Referring now to FIGS. 6-7, the distal end portion of elongate member104 will be discussed. Elongate member 104 defines penetrating end 156which is characterized by having an irregular shaped nose 158 withrounded tip 160. In particular, nose 158 is generally tapered inconfiguration defining a complex curved arrangement. In a first profileof nose 158 depicted in FIG. 6, the nose 158 includes opposed concavesurfaces 162. In a second profile (rotated) 90° as depicted in FIG. 7,nose 158 defines convex surfaces 164. This alternating concave andconvex arrangement provides a substantially reduced profile (incross-section) compared to conventional conically shaped obturatorsthereby providing an enhanced ability to penetrate or pass throughtissue layers. Various radii of curvature are contemplated. Rounded tip160, by its arcuate configuration, minimizes the potential of undesiredor unintended piercing of tissue. Alternatively, it is envisioned thatrounded tip 160 may be more pointed to also pierce tissue if desired.

Penetrating end 156 is substantially hollow to receive the distal end ofendoscope 200. Penetrating end 156 is fabricated from a biocompatibletransparent material including an optical glass or optical polymericmaterial and may be either a separate component or integrally formed,e.g., monolithically, with elongate member 104. Elongate member 104 maybe fabricated from the transparent or opaque material, desirably abiocompatible metal or plastic. Penetrating end 156 is adapted to passthrough tissue and may also be capable of cutting or piercing throughtissue if desired.

The components of the optical access apparatus may include any suitablebiocompatible metal such as stainless steel and titanium and its alloys.Alternatively, the optical access apparatus may include a polymericmaterial such as polycarbonate, polystyrene, etc. and manufactured viaknow molding techniques. Elongate member 104 may be transparentthroughout its entire length. Alternatively, only penetrating end 156 ofelongate member 104 may be transparent.

The use and function of the system 10 will now be discussed. Inlaparoscopic surgery, the abdominal cavity is insufflated with asuitable biocompatible gas such as, e.g., CO₂ gas, to insufflate thebody cavity and lift the body cavity wall away from the internal organstherein. The insufflation may be performed with an insufflation needleor similar device as is conventional in the art. Thereafter, an incisionis made in the outer epidermal surface of the abdominal cavity. Theincision is preferably small, for example, within a range from 2 to 7mm, and may be made with a scalpel etc. Thereafter, endoscope 200 ofsystem 10 is positioned within optical access apparatus 100 and advancedsuch that the distal window of the endoscope 200 is adjacent the nose158 of elongate member 104. FIGS. 8 and 9 illustrate the relationship ofendoscope 200 within optical access apparatus 10. In FIGS. 8 and 9,manual member 106 and collet 108 are in an initial position permittingendoscope 200 to advance within elongate member 104. When endoscope 200is at the desired position within access apparatus 100, e.g., when thedistal objective of the endoscope 200 is within or adjacent nose 158 ofelongate member 104, the endoscope 200 is then secured at the desiredlocation by manipulating the holding mechanism as discussed below.

With reference now to FIGS. 10 and 11, to secure endoscope 200, manualmember 106 is rotated in the direction of the directional arrows “Z”.Rotation of manual member 106 causes corresponding rotation of collet108 through the receptive arrangement of cam pins 130 of the collet 108within internal slots 120 of the manual member 106. Concurrently withthe rotation of collet 108, cam pins 130 traverse cam slots 152 ofelongate member 104, which drives collet 108 in a distal or downwarddirection as shown by directional arrows “B”. It is noted that cam pins130 also traverse internal slots 120 (i.e., move in a distallongitudinal direction) of manual member 106 to permit collet 108 tomove distally relative to manual member 106. During distal movement ofcollet 108, camming surface 122 of manual member 106 cooperates withcamming surfaces 128 of collar sections 124 a to cause the collarsections 124 a to flex inwardly and compressively engage the endoscope200 and frictionally secure the endoscope 200 within access apparatus100.

With reference to FIG. 12, the assembled system 10 is then introducedwithin the small incision “i” by positioning nose 158 of elongate member104 within the incision and advancing the system 10 through the incisionand the underlying tissue structure. Nose 158 is advantageouslydimensioned to penetrate and dissect the tissue along its path desirablyin a non-traumatic fashion. During advancement of system 10, endoscope200 is utilized to view the path along which the system is advanced toensure that any underlying tissue or organ site is prevented fromcontact with the access apparatus 100 and also to confirm entry withinthe body cavity. Once system 10 is positioned at the desired locationrelative to the abdominal cavity, endoscope 200 may be used to monitorthe desired surgical procedure being performed within the cavity. In thealternative, endoscope 200 may be inserted into and secured in theaccess apparatus 100 after the access apparatus 100 has been used topenetrate tissue.

Referring now to FIGS. 13-15, there is illustrated an alternateembodiment of the optical access apparatus for use in the system 10 ofthe present disclosure. Optical access apparatus 300 is substantiallysimilar to access apparatus 100 of FIGS. 1-12, and possesses housing 302and elongate member 304. Housing 302 consists of manual member 306,collet 308, skirt 310, flange extension 312, and housing plate 314 withthe components assembled together to define a single unit. Manual member306 is substantially identical to manual member 106 of access apparatus100 but further defines internal cam shelves 316 (four are shown) asbest depicted in FIG. 16, which replaces camming surfaces 122 of manualmember 106 of the aforedescribed access apparatus 100. Manual member 306is adapted to rotate about longitudinal axis “a” and relative to collet308. In this embodiment, collet 308 is stationary within housing 302,i.e., it does not rotate with manual member 306.

As best depicted in FIGS. 14 and 15, collet 308 includes proximal collar318 having four collar sections 318 a with adjacent sections 318 aseparated by slots 320. (In FIG. 15, housing 302 is shown without manualmember 306 mounted to collet 308.) Each collar section 318 a has opposedouter grooves 322 arranged in a manner such that respective grooves 322of adjacent collar sections 318 a, in effect, define a recess across theadjacent sections 318 a. Grooves or recesses 322 accommodate cam shelves316 of manual member 306 when in the initial position of manual member306. Outer cam surfaces 318 b are defined between grooves 322. As willbe appreciated, during rotation of manual member 306, cams shelves 316of manual member 306 traverse grooves 322 and engage cam surfaces 318 bto bias collar sections 318 a inwardly into secured engagement withendoscope 200. Collet 318 further includes lower slots 324 in its outersurface which serve to secure the collet 318 within housing 302.

Referring now to FIGS. 17-19, in conjunction with FIGS. 13 and 14, skirt310 and housing plate 314 are substantially identical to thecorresponding counterparts of the embodiment of FIGS. 1-12, andreference is made to the foregoing description for detailed discussionof the structure and function thereof. However, with this embodiment, itis noted housing plate 314 includes two pairs of projections 146.Projections 146 of housing plate 314 are received within lower slots 324of collet 308 so as to secure and prevent rotational movement of thecollet 308.

Flange extension 312 replaces flange of the embodiment of FIGS. 1-12,and is a separate component attached to elongate member 304 bymechanical means. Flange extension 312 includes flange plate 326 andflange collar 328 extending from the flange plate 326. Flange collar 328defines central aperture 330 to permit passage of the endoscope 200.Flange collar 328 includes internal shelves 332 which are receivedwithin corresponding openings 334 in the proximal end of elongate member304 to fix the flange extension 312 to the elongate member 304 (FIG.18). Flange plate 326 rests on housing plate 314 and defines a pluralityof rectangular grooves 336 in its periphery and a plurality of spacers338 at the intersection with flange collar 328. Grooves 336 accommodateportions of locking tabs 340 extending from housing plate 314. Spacers338 serve to align collet 308. Flange plate 328 has two pairs of opposedslots 342 which accommodate projections 146 of housing plate 314.

With reference again to FIGS. 13 and 14, elongate member 304 issubstantially identical to elongate member 104 of the embodiment ofFIGS. 1-12, but, incorporates a separate penetrating end 344. In thisregard, penetrating end 344 is attached to elongate member 304 throughconventional means including adhesives, cements, bayonet coupling, or ina preferred embodiment, a snap fit arrangement consisting of a pluralityof internal projections 346 extending within elongate member 304, whichare received within correspondingly dimensioned openings 348 of elongatemember 304. Other means for connecting penetrating end are alsoenvisioned. Penetrating end 344 is transparent as discussed hereinaboveand is preferably identical in configuration to the penetrating end ofthe embodiment of FIGS. 1-12.

Referring now to FIGS. 20-22, the function and use of optical accessapparatus 300 will be discussed. The abdominal cavity is insufflated andthe incision is formed in the epidermal tissue. Endoscope 200 ispositioned within access apparatus 300 and advanced to a portion wherethe distal end of the endoscope is positioned within penetrating end344. Manual member 306 is rotated about the longitudinal axis “x” in thedirection of the rotational arrow “m” and relative to collet 308. Duringthis movement, collet 308 remains stationary while internal cam shelves316 of manual member 306 traverse grooves 322 of collet 308 to engageouter cam surfaces 318 b of collar sections 318 a. This camming actiondrives collar sections 318 a inwardly to the position depicted in FIGS.21 and 22. In this position, collar sections 318 a securely engage theendoscope 200. The system 10 is then used in similar manner to thatdescribed in the embodiment of FIGS. 1-12. Alternatively, endoscope 200is inserted into the access apparatus 300 and secured after the accessapparatus has penetrated tissue.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofpreferred embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

1-25. (canceled)
 26. An optical access apparatus for reception of anendoscope to permit visualization during passage through tissue, whichcomprises: an access member dimensioned for insertion through bodytissue, the access member defining a longitudinal axis and having alongitudinal opening for receiving the endoscope, the access memberhaving a penetrating end adapted to pass through tissue, the penetratingend being at least partially transparent to permit visualization oftissue with the endoscope. a locking collet coaxially mounted relativeto the longitudinal axis of the access member, the locking collet havinginternal surfaces defining an internal passage to permit passage of theendoscope; and a manual member coaxially mounted about the lockingcollet, the manual member adapted for rotational movement about thelongitudinal axis to compress the locking collet to reduce an internaldimension of the internal passage of the locking collet to thereby causethe internal surfaces of the locking collet to securely engage theendoscope, wherein the manual member includes internal cam shelves andthe locking collet includes alternating outer cam surfaces and grooves,the internal cam shelves being accommodated within the grooves when inan initial position of the manual member whereby upon rotationalmovement of the manual member to an actuated position the internal camshelves traverse the grooves to engage the outer cam surfaces formed inthe locking collet.
 27. The optical access apparatus according to claim26 wherein the manual member is fixed from longitudinal movementrelative to the access member.
 28. The access apparatus according toclaim 27 wherein the locking collet is fixed from longitudinal movementrelative to the access member.
 29. The access apparatus according toclaim 28 wherein the locking collet includes a collar having collarsections with adjacent sections separated by slots, the collar sectionsadapted to be deflected radially inwardly relative to the longitudinalaxis of the access member.
 30. The access apparatus according to claim26 wherein the access member includes a penetrating end dimensioned topass through tissue.
 31. The access apparatus according to claim 30 thepenetrating end is at least partially transparent to permitvisualization of tissue.
 32. The access apparatus according to claim 31wherein the penetrating end is closed and defines a general taperedconfiguration.
 33. The access apparatus according to claim 32 whereinthe penetrating end includes opposed concave surfaces and opposed convexsurfaces.
 34. The access apparatus according to claim 31 including anendoscope, the endoscope being the instrument.